Those of you who adhere to the so-called "three-second rule" for fallen food should know that science has now evaluated the quality of your hygiene. Researchers at Manchester Metropolitan University in England have been hard at work dropping things, and here's what they found: Whether you're being totally disgusting depends on the nutritional value of the food in question. Foods high in fat, salt, and sugar — your deli meats, candy bars, anything from a burger chain — are pretty safe to eat after being on the floor for three seconds, owing to the "anti-microbial" powers of those ingredients. But dried fruit and cooked pasta? No bueno. That stuff really soaks up bacteria the second it hits the deck. Mind you, we'd imagine the whole thing depends heavily on the dirtiness of the particular floor in question, so probably don't start eating French fries off a train platform. [HuffPo UK]